Keratin Complex Smoothing Therapy Keratin Complex Smoothing Therapy is the hair smoothing treatment that has been taking salons around the world by storm. Developed by Coppola in the USA, Keratin Complex Smoothing Therapy is finally in the UK and already has many fans. The Smoothing Treatment is an exclusive Keratin hair treatment that is only available from officially authorised salons who are specially trained to make your hair look beautiful. The treatment can turn hair that is a frizzy mess into a smooth, controllable and beautiful set of locks and the treatments last for months, not weeks!